


But You're Human Tonight

by Carmenlire



Series: Tumblr Prompts [26]
Category: Shadowhunters (TV)
Genre: Alternate Universe - Canon Divergence, Dom/sub Undertones, Established Relationship, Fluff and Smut, Happy Magnus Bane/Alec Lightwood, High Warlock of Brooklyn Magnus Bane, M/M, Plot What Plot/Porn Without Plot, Post-Episode: s03e10 Erchomai, Sex Magic, which is bullshit since I wrote this first part in february but whatever
Language: English
Status: Completed
Published: 2019-02-12
Updated: 2019-08-07
Packaged: 2019-10-26 14:05:41
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,536
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17747279
Author URL: https://archiveofourown.org/users/Carmenlire/pseuds/Carmenlire
Summary: He’s been teasing Alec for ages, watching raptly at the way his magic curls around Alec. It sparks along his skin, teasing and playful. Alec loves it and hadn’tthatbeen a lovely discovery for them both. Alec arches into the phantom touch, always craving more and Magnus is helpless to deny him-- to deny them both the overwhelming pleasure at being loved with everything Magnus is.Or, Magnus celebrates the return of his magic with Alec.





	1. Chapter 1

**Author's Note:**

> Prompt by Anonymous: Magnus loses control of his magic during sex.

Magnus shifts in the chair, gaze focused on the scene before him. Thunder rumbles distantly outside but it’s an afterthought, scarcely audible over the noises spilling from Alec’s mouth.

Choked off moans and muted whimpers. Magnus’s favorite sounds.

He watches as Alec’s hips shift, as he arches into the touch that trails along along his body-- circling a nipple, traveling over abs that stand out in stark relief, and finally wrapping around his cock, already hard and leaking and desperate.

Blue wisps of magic, an extension of Magnus himself. Lightning strikes the sky and Magnus feels the way his magic absorbs the energy, sees the way the wave of blue turn dense. It’s a rush that Magnus hasn’t felt in ages-- in far too long-- and he can tell by the way Alec jerks, gasping, that he can feel it too.

Magnus knows with agonizing familiarity just how intense that kind of touch is, how the body yearns for it even as it shies away. It’s a contrast that makes his own head dizzy with lust-- he can just imagine what’s going on in Alec’s.

“That’s it, darling,” he murmurs. “Let go.”

Alec spreads his legs further apart, a shameless demand, and Magnus doesn’t even think of denying his boyfriend.

With a negligent wave of his hand, the blue tendrils of magic slowly gather and move down, pausing over his perineum, before moving down to the tight ring of muscle that has Alec crying out.

“God,” he gasps. “ _Magnus_.”

“Already so desperate, aren’t you? Insatiable,” Magnus whispers, eyes greedily taking everything in, and he curls his fingers, the magic obeying his command. The pressure is similar enough to one finger, that first intrusion, that Alec’s cock jerks as a whine catches high in his throat.

Magnus watches from where he’s seated in the chair next to the bed. He watches the way his magic worships Alec. It’s both foreign and familiar and the dichotomy makes the breath wrench in his chest.

He and Alec had just started experimenting with this kind of play before-- before everything had gone so horribly wrong and he’d lost the most vital piece of himself. His magic has always adored Alec. From that very first moment when an unexpected shadowhunter had come to his defense, Magnus had felt a piece of his very soul reach out and wrap around Alec.

To lose that connection had been a different sort of grief altogether to the overwhelming mourning that had already choked him. For warlocks, sex magic was another level altogether. It took trust from all parties and a desire to share that piece of themselves. It was an intimacy that Magnus hadn’t granted himself in decades and to have that now, with Alec, feels like coming home.

Now that Magnus has regained his magic, now that he finally feels whole, he wants to celebrate. He wants to love Alec with everything he is and everything he has and Alec had understood. Magnus had watched as Alec’s eyes had darkened at his request, as he’d nodded sharply before leaning down and kissing Magnus to within an inch of his life.

 _Yes_ , he’d muttered hoarsely. _Please_.

So, Magnus had moved them to the bedroom. He’d watched, greedy, as Alec had stripped. His boyfriend hasn’t quite mastered the art of the strip tease yet but his perfunctory movements still makes Magnus’s mouth flood in want, still has Magnus exercising more control than he should need to take things slow.

They have all night, after all, and Magnus doesn’t want this over too fast-- for either of them.

He’s been teasing Alec for ages, watching raptly at the way his magic curls around Alec. It sparks along his skin, teasing and playful. Alec loves it and hadn’t _that_ been a lovely discovery for them both. Alec arches into the phantom touch, always craving more and Magnus is helpless to deny him-- to deny them both the overwhelming pleasure at being loved with everything Magnus is.

Long minutes later, Alec is covered in a fine sheen of sweat. His breathing is harsh in the silence of the room, hair damp and runes standing out starkly on his pale skin.

He’s a feast laid out just for Magnus and it’s time to join in.

Standing, Magnus’s magic trails down Alec’s thighs. He works on unbuttoning his shirt as he watches the way Alec fidgets. His hips keep shifting like he just can’t stay still and Magnus watches as a large drop of pre-come drips onto his stomach, catching the muted light.

Magnus wants but tells himself to calm down, to savor this scene just a while longer.

“What do you want, darling,” he asks conversationally. He could be asking what Alec wants for dinner for all the intensity in his voice.

Alec’s eyes open, those brown eyes glowing with hunger and heat that makes Magnus’s gut clench in dizzying lust.

“You,” he says hoarsely. He bites down on his lip, swallowing a low moan as Magnus tightens the magic around his ankles and tugs them just a few inches further apart. It doesn’t do much but reveal his intention and Alec’s obviously on board as he manages to get out, “I just want you, Magnus. Your fingers, your mouth, _Angel_ , your cock. Just anything, _please_.”

Shrugging out of his shirt, Magnus waves it. . . somewhere. He doesn’t quite have the higher brain function to place it somewhere distinct and it’s such a rush that he can even use his magic for such a mundane, casual gesture that he doesn't place too much on the particulars.

“Ask and you will receive, Alexander.”

Magnus kneels on the bed between Alec’s spread out thighs and places his hands on his boyfriend’s knees. Ducking down, he kisses the inside of Alec’s knee, over a ticklish spot, and smiles as Alec huffs out a laugh.

His eyes focus on the shameless display before him and he licks his lips unconsciously, unaware of it until a groan is punched out of Alec as his hips arch, offering himself to Magnus in the most explicit way.

Reaching out, Magnus swipes a thumb through the pre-come that’s accumulated, rubbing it into Alec’s skin.

His magic coalesces and moves up Alec’s body, making them both shudder as they watch a blue wave travel past his hips, up his stomach. It gathers around the base of Alec’s throat and Magnus sees the way Alec’s eyes darken at the realization of what Magnus has planned. They’ve done this a few times, the conventional way, and the way Alec submits, the way he leans into the pressure never fails to push Magnus perilously close to the edge.

“Is this alright, darling? Give me a color.”

“Fuck, green, babe. So green,” Alec gasps, his voice already wrecked no matter that Magnus hasn’t even done anything yet.

Humming, Magnus collects the magic, tightening it imperceptibly around his love’s throat and he watches as Alec tips his head back, as his cock jerks at the faint pressure.

His gaze is glued to the thin line of blue around Alec’s throat, at the way it contrasts so beautifully with the stark black of his deflect rune.

Lightning cracks in the sky and his magic sparks with it. Alec’s mouth opens on a breath and Magnus reaches out. He sweeps a thumb over Alec’s lush bottom lip, leaving sparks in his wake. 

They both groan when Alec’s tongue swipes over his thumb, when he closes his mouth and sucks, groaning desperately as magic bursts on his tongue, bright and addicting.

Leaning over Alec, Magnus pulls his thumb out and reaches down between his thighs, turning the saliva into something warm and much more suitable for what he has planned next.

With his other hand, he trails a finger over Alec’s neck, over that damned rune, and then follows the line of magic that rests just over where his pulse is hammering away at the base of his throat.

He slips two fingers into Alec’s ass without warning, twisting them and relishing the choked sounds spilling out of his boyfriend’s mouth.

Bringing his lips to Alec’s ear, he whispers, “Know what I want, darling?”

He waits until Alec nods jerkily before he continues, “I want you to make me yours. I want to feel your cock in me and I want to ride you until we both can’t stand tomorrow. I want you to fuck me like you mean it, until all I can remember is your name. But that’s for later,” Magnus murmurs, grinning as he feels Alec thrust helplessly against his thigh, rough and desperate.

“Do you know what I’m going to do first, though? Before you come in me, before I let you lick your own come out of my ass, do you know what I’m going to do? I’m going to _make you mine_.”

Magnus punctuates his words with a sharp thrust of his fingers. Alec cries out and clenches down on the digits and Magnus pulls back to watch as he fingers Alec, as his boyfriend arches up for more.

“Oh God, Magnus. _Yes_. Please, yes.”

“I’m going to fuck you with my fingers and then if you’re good, I might just fuck you with my tongue. And _then_ , just when I feel you tighten around me, when you’re so close to the edge that you can’t see straight, so close that it’s the best kind of pleasure-steeped pain, when everything in you yearns to fall, I’m going to pull away.”

Alec sobs out a breath, and Magnus adds a third finger, letting his magic wander around Alec’s body, pressing firmly down on his nipples, moving down to wrap around the base of Alec’s cock, the head of it red and swollen and leaking in a constant stream as Alec bears down on Magnus’s fingers, hips twisting to keep the pressure constant.

“That’s when I’m going use my magic to bind you. Your beautiful wrists wrapped in blue, your breath choked off because of my magic-- because of me. Because I’m the fucking High Warlock of Brooklyn and you’ve given yourself to me as surely as I belong to you. You want this, darling, and Lilith knows that I love seeing you draped in my power and strength. You’re beautiful always but never more so when you give me this-- your submission, your trust.”

Magnus worries for a moment that he’s pushed Alec too far, that his words and his fingers alone will tip Alec over the edge and he pulls out immediately, watching as Alec’s hole desperately closes around nothing, as a high-pitched whine escapes him. He presses a hand to his own front, trying to stave off his own reaction to see Alec so lost in his own pleasure.

 _Jesus Christ_ , he thinks. At this rate, they both need to slow down.

Trailing soothing hands over Alec’s thighs, Magnus does that for a few minutes until Alec isn’t quite so close, until their breathing’s evened out just a little.

“That’s it,” he murmurs. “Nice and easy, darling.”

Leaning over Alec, Magnus lets his necklace fall onto his boyfriend’s chest with a musical whisper. Alec’s head is already tilting up, mouth open for his kiss and Magnus loses himself in the lushness of Alec’s mouth. 

A warm breeze blows through the room smelling of rain and Magnus feels his magic surging in him, a riotous wave. It’s always been volatile, a steady well of power to draw on but it also drew energy from the elements. Magnus had a certain fondness for thunderstorms in particular and it’s times like now that he relishes the full potential of his magic.

He’s always in the utmost command of it, though-- he learned early and well how to control his magic to protect both him and those around him.

Still, there are occasions when he releases it from its ironclad leash. More often than not these days, it’s times just like this-- when Magnus is overwhelmed by the love and desire that crashes through his system and he doesn’t even think of denying himself the pleasure of watching Alec fall apart at his hands, at the magic that wraps around him, devout in its own way to Alec.

Magnus nips at Alec’s bottom lip, soothing the sting with his tongue. He doesn’t know how long he spends on Alec’s mouth, lazy and slow and so damn deep his toes curl in the sheets.

Kissing Alec was a revelation and it’s one of Magnus’s favorite ways to spend an afternoon, whiling away a few hours until his mouth is numb and slick, until he can’t breathe without moaning.

It takes a herculean effort to pull away from Alec but Magnus is rewarded when his love opens hazy eyes, when he takes in Alec’s swollen mouth and sees the sweep of heat that brushes high across those lovely cheekbones.

Alec looks the very picture of debauched but Magnus is just getting started. Alec can look so much worse and Magnus can’t wait to wreck him a little more before the favor’s returned in spades.


	2. Chapter 2

Alec groans against his shoulder and Magnus can’t resist hiding a smug smile in their sheets. It’s severely dampened, however, by the fact that he’s yet to catch his own breath.

He feels Alec trail a path of kisses across his back and he hums a little, the smile turning into something quieter. The heat that had flared so hot between them earlier is finally spent and now it’s warmth, slow and sweet, that curls through him as his boyfriend noses along his skin.

The rain has long since passed and silence falls over them. Distantly, Magnus wishes he never had to move from this spot. Right here, with Alec, is exactly where he’d choose to stay, forever, if only he could.

But alas, he thinks with a little sigh, he knows he and Alec need to get up. Sweat cools on his skin and a dozen little aches make themselves known.

 _Five more minutes_ , he tells himself. Magnus feels well and truly used but God, he loves it. It’s something that had surprised and delighted Alec in equal measure, discovering Magnus’s tendency to sink into the aftermath instead of immediately cleaning up and disappearing any trace of what they’d just done.

Shifting, just a little, Magnus buries his face in his pillow. It smells like them and he sighs again, content in the best way. Alec moves behind him until he’s resting his head between Magnus’s shoulders and his stubble scratches over still-sensitive skin, makes Magnus shiver though the sparks die out as soon as they’ve had a chance to form.

He’s well and truly spent.

Exhaustion pulls at him and Magnus knows that he could fall asleep just like this, with Alec a long line of warmth over him, pressing him into the mattress. 

Still.

There’s a restless energy simmering just under the surface and it's familiar. It fills him with a quick joy, makes his heart skip a beat. He feels power-- his strength, his saving grace-- flow through his veins and it makes all the difference in the world.

Magnus is just set to call his magic to him-- he has a sudden need to see cobalt and azure-- when Alec lets out an incredulous laugh.

“Holy shit, babe.”

Grunting-- words seem like far too much effort when Alec’s just fucked his brains out-- Magnus instead groans when he feels Alec pull away. Cool air drifts over him and it feels like the worst sort of betrayal.

“Alexander, get back here. I’m not done with you yet.” Magnus’s voice is muffled as he’s still face down in bed but he hears Alec laugh again and he’s delighted when it comes out an inelegant snort.

He can just imagine his boyfriend shaking his head down at him and it’s ridiculous but that predictability makes his heart squeeze in his chest. He knows what Alec looks like when he’s amused, when he’s biting back a biting comment; when he’s so lost in his own pleasure that he only knows Magnus’s name.

It’s a heady feeling to realize how much he knows about Alec-- and how much he’s allowed Alec in so that this shadowhunter, this man who isn’t perfect but tries so hard, knows him just as well.

Alec doesn’t give him a chance to mull over the quiet bomb that’s unsurprising but no less unexpected. Before he quite knows what’s happened, his boyfriend has turned Magnus over. When his back hits the bed, Magnus scowls though it’s with little heat.

Instead, he takes this chance to study Alec and goddamn but his boyfriend is always vision but never more so than when he’s been loved and loved well by Magnus.

His cheeks are still flushed and there’s a trail of bruises down his neck, along his collarbones. His hair is a fucking bird’s nest, dark and messy, and Magnus has an unforgivably foolish wish to drown in those brown eyes he loves so much.

They’re full of everything he’s ever wanted, love and desire and happiness making them glow with a special kind of vivacity.

He’s half a mind to pull Alec down to him, wants to lose himself in that lush mouth, but Alec has other ideas.

Magnus raises a brow when his attempts to pull Alec closer are met with resistance.

Alec sends him an arch look back before jerking his head toward the rest of the bedroom. “How does it feel?”

“How does what feel, darling,” Magnus asks absently as his gaze zeroes in on Alec’s mouth.

Alec’s voice is soft as he clarifies, “How does it feel to be back?”

At the words, Magnus’s eyes snap up to his. Once more, Alec gestures toward their bedroom and it’s only when he takes in the space that Magnus’s own eyes widen.

A maelstrom of feeling punches him in the throat, clutches his ribs until he swears he hears them cracking.

Their bedroom is a mess. It looks like a tornado went through the place.

The curtains have fallen to the floor in a mountain of rich crimson brocade. A lamp has been turned over, it’s weak light casting heaving shadows on the walls.

Two-- no three-- vases lay in jutting shatters on the bare wood floor. Magnus wonders that he should feel regret-- he’d quite liked the jade one, after all, as it was a centennial birthday gift from Catarina-- but he feels nothing but pride, satisfaction blazing through him at the very real, physical signs that his magic is returned to him in all its might.

As he turns to look back at Alec, he sees the ceiling and a different kind of joy suffuses him for there’s _light_. He hadn’t noticed, so focused on Alec, but the room glows in twining shades of blue. This has only happened a few times before and Magnus is struck dumb once again at the evidence that his magic is so happy to be back with him again-- that it loves Alec enough to put on such a display, to use the independence Magnus grants it to show Alec just how much he makes him feel.

It’s a connection that had flared so hot just a few minutes ago that Magnus still smells the sparks in the air. Now, as he turns into himself, he feels his magic simmering instead of shuddering. It’s content now in the quiet, happy as Magnus himself to wrap around Alec and bathe the both of them in a wave of warmth.

Meeting Alec’s eyes, Magnus sees the same awe and devotion that stole his breath the first time Alec saw his mark. It’s overwhelming to be loved so much but damned if Magnus wouldn’t move heaven and every realm of hell to keep this feeling alive in this chest.

Mouth lifting in a faint grin, Magnus demurs. “So maybe I lost control. What of it?”

A challenge glints in his eyes and he watches as Alec’s own darken at the declaration.

This is far from the first time this has happened but it’s been so long it feels new all over again. Alec leans close and Magnus’s breath catches but he doesn’t close the distance between them, instead asking in a low tone as he noses over Magnus’s cheek, “ _So_ , how does it feel, High Warlock Bane? How does it feel to be back?”

The words hit Magnus and he closes his eyes against the onslaught they summon. He takes a bracing breath as he tries to think of the answer to Alec’s question.

How does it feel to have his magic-- a piece of his soul-- returned to him? How does it feel to see its effects all around them? And by God, how does it feel to share it all with the man he’d trade it for, all over again?

When he opens his eyes, it’s to see Alec smiling down at him like he can read his mind. The silence stretches out and when Magnus answers it’s barely a whisper as he grins up at his love.

“Free,” he says in the space between their lips. “I feel free.”

**Author's Note:**

> catch me on tumblr or twitter @carmenlire!


End file.
